Implementation of graphics system for the representation and manipulation of biochemical objects is being done at various levels of hardware, system software and user software. Work on the link between the DECsystem-10 and the graphics system was brought to completion. Modifications to the surface generation algorithm resulted in the removal of a limit of 1800 displayable atoms. The system can now do hidden sphere calculations for between 10,000 and 15,000 atoms. Programs were developed for the interactive modeling of up to 300 atoms at a time. Modeling of larger structures is handled by scooping out sections within the 300 atom limit. This programs have been applied to the modeling of drug-protein interactions and drug-nucleic acid interactions. Implementation of a digitizing microscope densitometer is proceeding slowly at the system software and hardware testing levels.